<mat-card>
  <mat-card-title>运营商分布</mat-card-title>
  <mat-card-content>
    <ngx-charts-pie-chart *ngIf="data?.length" [scheme]="colorScheme" [results]="data" [legend]="showLegend"
      [explodeSlices]="explodeSlices" [labels]="showLabels" [doughnut]="doughnut" (select)="onSelect($event)">
    </ngx-charts-pie-chart>
  </mat-card-content>
</mat-card>